Your Highest Heat Index Temp/Lowest Windchill Temp! (ice, recorded, temperatures)

[tijlover]

Granted, this could be more challenging to come up with, but try your best!

Generally, in Las Vegas when our humidity can go as low as 3%, for the Heat Index, you merely shave off 5-10 degrees from the real temperature. And when that happens in the summertime, with a 110F day, and I see Atlanta with 95 degrees and ungodly humidity, I want to send Atlantans a sympathy card! They're suffering much more than we are!

We suffer the most here during our "monsoon" season, end of July and part of August, when our humidity levels can rise to 20-30-40%, and with a temp of 100F?

And, in the winter here, when it falls to 25 degrees in January, and along with a clear blue sky night and with one of our wind blasters at 40MPH, we're suffering a windchill of -13F, and then I envy my brother in Minneapolis with the comfort of 25 degrees, no wind and clouds in the skies!

We all know how deceptive real temp's are!!! Wind is oftentimes overlooked, and humidity levels!

I'm expecting some surprises here!

[Humid Subtropical]

This blog has a bit of info:

"But it was during the July heat wave of 1995 that the highest dew point of all was measured in the Upper Midwest: 90°F/32°C at Appleton, Wisconsin at 5 p.m. on July 13th of that summer. The air temperature stood at 101°F/38°C in Appleton at that time leading to a heat index reading of 148°F/64°c, perhaps the highest such reading ever measured in the United States."

Record Dew Point Temperatures | Weather Underground

"The absolute highest dew point recorded in the region and therefore the world (of which I am aware) was 95°F/35°C at Dhahran, Saudi Arabia at 3 p.m. on July 8, 2003. The dry bulb temperature stood at 108°F/42°c at the time, so theoretically the heat index was 176°F/80°C."

[theunbrainwashed]

About 108°F/-30°F for me

[Joe90]

I've never seen a heat index for here before. High temperatures here come with low relative humidity, so the heat index would be lower than the actual temperature, so about 35C

No windchill forecasts either, but frosty mornings here have a downslope wind, -3C with a 15 kph wind gives about -9C windchill, which would be about the coldest most years.

[Morningrise]

I don't remember the exact numbers, but I know the highest heat index I've experienced was a little over 40°C and the coldest windchill a little under -50°C.

[Glacierx]

In Canada we use the humidex scale, which gives higher values than the American heat index. The humidex has exceeded 50°C (122°F) 8 times that I'm aware of:

1. Castlegar, BC: 53.4°C (128°F) in July of 1961
2. Carman, MB: 52.6°C (127°F) in July of 2007
3. Windsor, ON: 52.1°C (126°F) in June of 1953
4. Estevan, SK: 52.0°C (126°F) in July of 1981
5. Indian Head, SK: 51.1°C (124°F) in July of 2007
6. Toronto: 50.9°C (124°F) in July of 1995
7. Toronto (Int'l A): 50.2°C (122°F) in July of 1995
8. Brooks, AB: 50.1°C (122°F) in June of 1997

[Kamsack]

be careful when talking about past wind chills.....in 2001 the US and Canada implemented a new wind chill formula.....so cannot compare wind chills post 2001 to prior to 2001....

GOLDEN GATE WEATHER SERVICES- Wind Chill, New and Old

The same condiitions (say 5 with a 30 mph wind) produces a wind chill of -19 using the current formula...but the old one prior to 2001 would give a wc of -40F. So those very low wind chill values of the past may never again be achieved. I believe in 96 Minot ND had a wind chill close around -80 or so.

The reason for the change is to improve upon the current index, which is based on the 1945 Siple and Passel Index. During the Fall of 2000, the Office of the Federal Coordinator for Meteorological Services and Supporting Research (OFCM) formed a special group consisting of several Federal agencies, MSC, the academic research community (Indiana University-Purdue University in Indianapolis (IUPUI), University of Delaware, and University of Missouri), and the International Society of Biometeorology.

[Kamsack]

correction to above...coldest wind chill in ND was at Minot AFB in 1996 when it was -104 on the old scale....which would be around -70/-75 on new scale.

[tijlover]

I've been using the Heat Index/Wind Chill Tables from the People's Almanac. With this, with 5F and 30MPH, I also come up with -40F windchill.

More scary is the Heat Index. 100F with 80% humidity = 144F! Yikes! And how many times has it reached near 100 on the East Coast in summertime, with sky-high humidity!!

Living in the desert, where people underestimate how cold it can get here, I always shave off 8 degrees from the temp, whether there's wind or no wind! When you buy plants at a nursery here in either Phoenix or Las Vegas, it will say: Protect your plants if it falls below 40F. So! It freezes at a different temp here, particularly if the sky is free of clouds.

There were a number of mornings, when I lived in Phoenix, and it never got to 32F, and when I turned the garden hose on, ice chunks would come out!

So my People's Almanac Index's are now obsolete!

[Kamsack]

Originally Posted by tijlover

I've been using the Heat Index/Wind Chill Tables from the People's Almanac. With this, with 5F and 30MPH, I also come up with -40F windchill.

More scary is the Heat Index. 100F with 80% humidity = 144F! Yikes! And how many times has it reached near 100 on the East Coast in summertime, with sky-high humidity!!

Living in the desert, where people underestimate how cold it can get here, I always shave off 8 degrees from the temp, whether there's wind or no wind! When you buy plants at a nursery here in either Phoenix or Las Vegas, it will say: Protect your plants if it falls below 40F. So! It freezes at a different temp here, particularly if the sky is free of clouds.

There were a number of mornings, when I lived in Phoenix, and it never got to 32F, and when I turned the garden hose on, ice chunks would come out!

So my People's Almanac Index's are now obsolete!

For current wind chills....yes anything that uses tables before the change in Nov 1, 2001 would be obsolete....when comparing years after 2001 to ones prior. It doesnt make that data bad....but for comparison to current you cannot use it.

For heat indices....I am not aware of any changes over the years....so what you see from a old chart is the same as now.